Chinese e-commerce giant Alibaba Group Holding Ltd. will report earnings for its fiscal first quarter that ended June 30 on Thursday before the U.S. market opens. Here’s what you need to know.

Earnings Forecast: Alibaba is expected to report net income of 9.9 billion yuan ($1.5 billion), a decrease of 68% from a year earlier, according to estimates from 19 analysts polled by Thomson One Analytics. In the year-earlier quarter, Alibaba reported net income of 30.82 billion yuan, boosted by a one-time investment gain related...